Using significant figures, what would the answer be?

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I've been learning about significant figures and I have a few questions.

When you multiply/divide, the number of significant figures in the answer should be the same as the term with the least number of significant figures. But what about in a situation where the answer just has more significant figures?

For example, what if you have 12^2. This would be the same as 12 x 12, right? And if that's true, then the answer should have only 2 significant figures. So would I round the answer(144) to 140 so it has the correct number of significant figures?

Also, in my physics book, it says

Convert the following to SI units:

a. 60 mph

b. ...

c. ...

But it seems as if they're treating 60 mph as having 2 significant figures because their answer is 27 m/s. But from what I've learned, 60 mph only has 1 significant figure and therefore the answer would be rounded to 30 m/s

Can someone please shed some light on both these situations?

Thanks!